Projection processor for projective display system

ABSTRACT

A projection processor for a projective display system includes: a receiving circuit and an image adjustment control circuit. The receiving circuit is configured to receive information provided by a hardware element within a projection source device of the projective display system. The image adjustment control circuit is coupled to the receiving circuit, and configured to adaptively control an image adjustment on an input image to generate the source image according to the information.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 62/003,260, filed on May 27, 2014, and U.S. Provisional Application No. 62/034,952, filed on Aug. 8, 2014. The entire contents of the related applications are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates generally to projective display system, and more particularly, to a projection processor that is operable to adaptively control projection function and image adjustment of a projective display system.

BACKGROUND

A stereo display is a display device capable of conveying depth perception to the viewer and reproducing real-world viewing experiences. The stereo display can be implemented with different technologies. However, technologies nowadays respectively have some disadvantages. Stereoscopic display technology has the disadvantage that the viewer must be positioned in a well-defined spot to experience the 3D visual effect and the disadvantage that the effective horizontal pixel count viewable for each eye is reduced by one half as well as the luminance for each eye is also reduced by one half. In addition, glasses-free stereoscopic display is desirable but glasses-free stereoscopic display currently leads to poor user experience. Holographic display technology has a great viewing experience but the cost and the size is too high to apply to mobile devices.

SUMMARY

It is one objective of the present invention to provide projection processor, which can be used to implement a projective display system of low cost, high projection quality, highly integrated and rich user adjustability. The projection processor of the present invention is able to adaptively control the project and make the projection quality meet requirements of different applied conditions of the projective display system.

According to one embodiment of the present invention, a projection processor for a projective display system comprises: a receiving circuit and an image adjustment control circuit. The receiving circuit is configured to receive information provided by a hardware element within a projection source device of the projective display system. The image adjustment control circuit is coupled to the receiving circuit, and configured to adaptively control an image adjustment on an input image to generate the source image according to the information.

These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A and FIG. 1B respectively illustrate an oblique view and side view of a projective display system.

FIG. 2 illustrates a relation between the projection processor of FIG. 1 and an application processor.

FIG. 3 illustrates an image flipping adjustment controlled by the projection processor of the present invention.

FIG. 4 illustrates how a geometric distortion of a virtual image occurs.

FIG. 5 illustrates selecting the image adjustment algorithm based on available bandwidth of the memory according to one embodiment of the present invention.

FIG. 6 illustrates selecting the image adjustment algorithm based on battery life according to one embodiment of the present invention.

DETAILED DESCRIPTION

Certain terms are used throughout the following descriptions and claims to refer to particular system components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not differ in function. In the following discussion and in the claims, the terms “include”, “including”, “comprise”, and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ” The terms “couple” and “coupled” are intended to mean either an indirect or a direct electrical connection. Thus, if a first device couples to a second device, that connection may be through a direct electrical connection, or through an indirect electrical connection via other devices and connections.

Projective Display System

FIG. 1A and FIG. 1B respectively illustrate an oblique view and a side view of a projective display system. As shown by figures, a projective display system 100 comprises a base 110, a projection source device 120 and a projection surface 130 and an optional optical adjustment unit 140. In some embodiments, the projection source device 120 may be rotatably mounted, for example, on the base 110. In some other embodiments, the projection source device 120 may be detachably placed in a carrier, which may be rotatably mounted, for example, on the base 110. The projection source device 120 may be a portable device, such as smartphone, tablet, touch controlled device, or any other electronic device with a display panel or a projection source component. The projection source device 120 comprises: a projection source component 122 and a projection processor 124.

The projection source component 122 is configured to display a source image thereon. The projection source component 122 may be an organic light-emitting diode display panel, a liquid crystal display panel, or any other passive or active display panel. In some other embodiments, the projection source component 122 may be a solid-state (laser or LED) light or any other type of light source.

The projection processor 124 is configured to adaptively control an image adjustment on an input image to generate the source image. One purpose of the projection processor 124 is to maintain a good projection quality of the projective display system. The projection processor 124 could be implemented with a general-purpose processor or dedicated hardware. Please note that, the position of the projection processor 124 in FIG. 1A and FIG. 1B is just for the purpose of illustration rather than limitations.

The projection surface 130 could be made of transflective material or non-opaque material (e.g. transparent/semitransparent material.) The projection surface 130 may be rotatably attached, for example, to the base 110. Also, projection surface 130 could be flat or curved. The projection surface 130 is configured to mirror or partially reflect the source image that is projected from a first side of the projection surface 130 to form a virtual image on a second side that is opposite to the first side, thereby forming a stereo viewing effect. In detail, some intensity of the source image may be projected through the projection surface 130, and some other intensity of the source image may be reflected by the projection surface 130, such that the projection surface 130 partially reflects the source. As a result, a user may see the virtual image displayed on the projection surface 130 or floating behind the projection surface 130, thereby forming a stereo viewing effect, especially for the source image with 3d effect.

The optical adjustment element 140 may be rotatably attached to and detachable from the base 110. The optical adjustment element 140 may optically adjust forming of the virtual image on the projection surface 130. In various embodiment of the present invention, the optical adjustment element 140 could be a single lens or a compound lens.

Projection Processor

FIG. 2 illustrates an application processor 200 of the projection source device 120 and a projection processor 124 according to one embodiment of the present invention. In various embodiments, the projection processor 124 could be embedded into the application processor 200. Alternatively, the projection processor 124 could be disposed in the projection source device 120 and external to the application processor 200. Alternatively, the projection processor 124 could be external to the projection source device 120. The projection processor 124 could communicate with the application processor 200 or the projection source device 120 through wired or wireless communication means.

The projection processor 124 controls the image adjustment on the input image to generate the source image that is optimized for projection according to information regarding various hardware elements in the application processor 200. In one embodiment, the projection processor 124 may comprise a receiving circuit and an image adjustment control circuit. The receiving circuit receives the information regarding various hardware elements in the application processor 200 or in the projection source device 120. The information could be transmitted from the application processor 200 or the projection source device 120 to the receiving circuit via wired or wireless communication means. The image adjustment control circuit is coupled to the receiving circuit, and adaptively controls an image adjustment on an input image to generate the source image according to the received information.

The application processor 200 may include at least one of a set of sensors 210, image signal processor 220, image encoder 230, video encoder 240, image decoder 250, video decoder 260, display processor 270, graphic engine 280, battery meter 290, and driver IC 300. The set of sensors 210 may include at least one of image sensor, proximity sensor, ambient light sensor and other types of sensors, which will be illustrated later in further details. The set of sensors 210 may provide information for the projection processor 124 to determine how to control the image adjustment on the input image. In addition, the projection processor 124 may also turn off the projection function of the projective display system according to the information provided by the set of sensors 210. Image data generated by the image signal processor 220, the image decoder 250, the video decoder 260, and the graphic engine 280 may be transmitted to the display processor 270. According to the received image data, the display processor 270 generates the input image and may send it to the projection processor 124 (via wired or wireless communication means). The image adjustment control circuit of projection processor 124 may control the image adjustment on the input image to generate the source image that is optimized for projection. The generated source image may be sent to the driver IC 300, and the driver IC 300 may accordingly drives the projection source component 122 to show or project the source image. The image adjustment may be directly performed by the projection processor 124. Alternatively, the image adjustment may be performed by the display processor 270, the graphic engine 280, the image signal processor 220 or other video processing units under control of the projection processor 124.

Signal line designated with dash lines represents unidirectional or bidirectional control path, the image adjustment control circuit of the projection processor 124 may use signal thereon to determine whether to perform the image adjustment, and/or instruct the other circuits to perform the image adjustment and how the image adjustment is performed.

Image Adjustment

In the following, several image adjustments for different purposes will be introduced. However, this is not intended to limit the present invention in scope. There could be other types of the image adjustments performed in other embodiments of the present invention.

An Image flipping adjustment is intended for flipping the input image. Due to a relative position of the projection surface 130 with respect to the projection source component 122, there could be an upside-down virtual image reflected to the eye of the viewer. Please refer to FIG. 3, when the top of the subject is close to the bottom of the projection surface 130, there could be an upside-down virtual image formed on or behind the projection surface 130. Therefore, the input image needs to be flipped such that the viewer can see the virtual image with correct orientation. The image flipping adjustment can let the input image flipped and have a flipped source image shown on projection source component 122. The image adjustment control circuit of the projection processor 124 could determine the relative position of the projection surface 130 with respect to the projection source component 122 by utilizing one of the set of sensor 210 to detect a magnetic unit attached to or embedded in the projective surface 130, and then determine whether to activate the image flipping adjustment, for example, according to the detection about the magnetic unit. FIG. 3 illustrates an image flipping adjustment according to one embodiment of the present invention. In some other embodiments, any other type of sensor may be utilized to detect if the orientation of the virtual image formed on or behind the project surface 130 is correct.

An image segmentation adjustment is intended for separating a subject from a background of an image. This can make the subject spotlighted. Image segmentation can be achieved as below. First, pick up a region of the subject as a region of interest in the input image, remove objects in the region outside of the ROI, and may fill the region outside of the ROI with a simple and/or darker color to generate the source image. As a result, the subject can be relatively brighter, more contrasted, or more vivid than the background.

An image enhancement adjustment is intended for enhancing the input image.

After the source image is mirrored or partially reflected by the projection surface 130 to form the virtual image, the virtual image could be less contrast, bright, and saturated compared to the source image. This is because the projection surface 130 is semi-transparent and semi-reflective due to transflective material. Some portion of light of the source image will pass through the projection surface 130 and may not be reflected to the view's eye. Hence, the projection processor 124 could perform or instruct other circuit inside or outside the projection processor 124 to perform image enhancement on the input image to generate a brighter, more contrast, and/or saturated source image to guarantee a good projection quality. This can lead to a favorable visual perception to the viewer.

A distortion correction adjustment is intended for geometric distortion correction. When the optical adjustment element 140 is not in parallel with the projection surface 130, the virtual image would be distorted in geometry. The image adjustment control circuit of the projection processor 124 may determine whether to activate the distortion correction adjustment and how the distortion correction adjustment is performed, for example, according to an angle 0(shown by FIG. 4). In addition, when the optical adjustment element 140 does not optically cover the full area of the source image displayed or projected by the projection source component 122, the virtual image could be incomplete to the source image. Hence, the distortion correction adjustment may be performed for correcting such distortions, such that a user may see an un-distorted virtual image, which looks like the original appearance of the source image, shown on or behind the projection surface 130 after distortion correction.

Algorithms for Image Adjustment

As the image adjustment control circuit of the projection processor 124 could adaptively control a variety of different image adjustments to meet different requirements, there is a need of providing a way of simplify the control of the image adjustment. In the invention, the image adjustment control circuit of the projection processor 124 may control the image adjustment based on selecting a proper image adjustment algorithm. The following Table A illustrates a set of predetermined image adjustment algorithms of the present invention.

TABLE A Index of Complexity Power consumption Projection Algorithms Level level quality level 1 5 5 5 2 4 4 4 3 3 3 3 4 2 2 2 5 1 1 1

As shown by Table A, different image adjustment algorithms corresponding to different complexity levels, power consumption levels, and projection quality levels. For image adjustment algorithm 1, it is most complicated and consumes power most, but the projection quality is best. For image adjustment algorithm 5, it is least complicated and consumes least power, but the projection quality is worst.

In different embodiments, the image adjustment algorithms may be not classified by complexity levels, power consumption levels, or projection quality levels. For example, in one embodiment, the image adjustment algorithms could be classified by the types of image adjustments that the image adjustment algorithms are respectively optimized for. For example, there could be one image adjustment algorithm which is optimized for image flipping while another which is optimized for image enhancement. Alternately, the image adjustment algorithms also could be classified by the type of image adjustment which is activated. That is, some image adjustment algorithms may not activate all the four types of image adjustments as mentioned above.

The image adjustment control circuit of the projection processor 124 could adaptively select a proper image adjustment algorithm according to different conditions to meet different requirements. When a condition changes, the image adjustment control circuit of the projection processor 124 can adaptively select a new suitable image adjustment algorithm for the new condition.

Please note that, the number of image adjustment algorithms that are listed on Table A is just for the purpose of illustration rather than limitations. Further, differences between the image adjustment algorithms are also not limitations. According to various embodiments of the present invention, there could be an image adjustment algorithm which consumes less power and have better projection quality than another one.

Determination of Algorithms

The image adjustment control circuit of the projection processor 124 could control the projection (e.g., determining whether to enable the projection function of the projective display system 100 as well as controlling the image adjustment on the source image on the projection source component 122) according to one type of the information including sensor information, hardware status, image context, and ISP parameters. Below are some embodiments.

Sensor Information

In one embodiment, the image adjustment control circuit of the project processor 124 selects the image adjustment algorithm according to a type of the projection source component 122. For example, an organic light-emitting diode (OLED) display panel features higher brightness and contrast than a liquid crystal projection source component 122. Hence, when it is detected the projection source component 122 is OLED panel (e.g., according to signal on the control path between the projection source component 122 and the receiving circuit of the projection processor 124), the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm that is not optimized for the image enhancement, or may not activate the image enhancement, thereby saving power and hardware resources of the projection processor 124 or application processor 200.

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to ambient light information provided by an ambient light sensor in the set of sensor 210. When the intensity of ambient light is detected high, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that activates the image enhancement to increase the brightness or contrast of the source image to cause the virtual image to be more visible to the viewer. On the other hand, when the intensity of the ambient light is detected low, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that activates the image enhancement to decrease the brightness of the source image to save the power. The “high intensity” and “low intensity” can be defined by thresholding or table-look-up.

In one embodiment, the image adjustment control circuit of the project processor 124 selects the image adjustment algorithm according to the information provided by a proximity sensor of the set of sensors 210, which may measure a distance between the projection source device 120 and the viewer. When the distance is detected short, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that causes the image segmentation to be performed more aggressively to have a good projection quality (since the user can clearly see all details in the virtual image when the distance is short). When it is detected the distance is long, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm which performs the image segmentation slightly to save power or hardware resources. The “short distance” and “long distance” can be defined by thresholding or table-look-up.

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to the information provided by a thermal sensor of the set of sensors 210, which may measure an internal temperature of the projection source device 120 or sense information corresponds to the internal temperature of the projection source device 120. When the temperature is detected high, the image adjustment control circuit of the projection processor 124 selects the image adjustment algorithm which is less complicated and/or consumes less power to avoid overheating issue. When it is detected the temperature is low, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that is optimized for the image enhancement and image segmentation to guarantee the best projection quality.

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to the information provided by an accelerometer or a G-sensor of the set of sensors 210, which may measure an acceleration of the projection source device 120. When the acceleration is detected high, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that does not activate any image adjustment or turns off the projection function of the projective display system 100 (e.g. turns off the projection processor 124) to save power and hardware resources because in such condition the viewer can hardly see the virtual image. When it is detected the acceleration is low, the image adjustment control circuit of the projection processor 124 may select a proper image adjustment algorithm and remain the projection function of the projective display system 110 enabled. The “high acceleration” and “low acceleration” can be defined by thresholding or table-look-up

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to the information provided by a gyroscope of the set of sensors 210, which measures an orientation of the projection source device 120. When the projection source device 120 is detected moving, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that does not activate any image adjustment or turns off the projection function of the projective display system 110 (e.g. turns off the projection processor 124) to save power and hardware resources because the viewer can hardly see the virtual image in such condition. When the projection source device 120 is detected not moving, the image adjustment control circuit of the projection processor 124 may select a proper image adjustment algorithm and remain the projection function of the projective display system 110 enabled.

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to the information provided by a pressure sensor of the set of sensors 210, which measures pressure (e.g., typically pressure of gases or liquids over the projection source device 120.) When it is detected that the projection source device 120 is pressed by the wind or physical object, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that does not activate any image adjustment or just turns off the projection function of the projective display system 110 (e.g. turns off the projection processor 124) to save power and to prevent the projection surface 130 stepping into a unstable state. When it is detected that the projection source device 120 is not pressed, the image adjustment control circuit of the projection processor 124 may select a proper image adjustment algorithm and remain the projection function of the projective display system 110 enabled.

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to the information provided by a global position system (GPS) device of the set of sensors 210, which may include time and position information regarding the projection source device 120. When it is detected that the current time is after the midnight, the image adjustment control circuit of the projection processor 124 may turn off the projection function of the projective display system 110 (e.g. turns off the projection processor 124). In some other embodiments, the current time may be determined or provided by any other method, which should not be limited in this disclosure. When it is detected the projection source device 120 is located in an office, the image adjustment control circuit of the projection processor 124 may turn off the projection function of the projective display system 110. When it is detected the projection source device 120 is located at home, the image adjustment control circuit of the projection processor 124 may select a proper image adjustment algorithm and remain the projection function of the projective display system 110 enabled.

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to the information provided by a heart rate sensor of the set of sensors 210, which measures the heart rate of a user of the projection source device 120. When it is detected a high heart rate, the image adjustment control circuit of the projection processor 124 selects the image adjustment algorithm that does not activate any image adjustment or turns off the projection function of the projective display system 110 (e.g. turns off the projection processor 124) because the user may be doing exercise. When it is detected a low heart rate, the image adjustment control circuit of the projection processor 124 could select a proper image adjustment algorithm and remain the projection function of the projective display system 110 enabled because the user may be in a steady state.

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to the information provided by a fingerprint sensor of the set of sensors 210, which provides identity information of different users. The projection processor 122 could therefore select a proper image adjustment algorithm for different users. For example, if a specific user prefers projection viewing, the projection processor 122 may select the image adjustment algorithm that has best projection quality. If the specific user does not prefer projection viewing, the projection processor 122 could turns off the projection function of the projective display system 110.

In one embodiment, the image adjustment control circuit of the project processor 124 may select the image adjustment algorithm according to the information provided by an ultraviolet (UV) sensor of the set of sensors 210, which measures the intensity of UV of the environment. When it is detected a high UV, the image adjustment control circuit of the projection processor 124 selects the image adjustment algorithm that is optimized for image enhancement or increases the brightness for good projection quality since the viewer may be currently in an outdoor environment. When it is detected a low UV, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm which maintains the brightness at a moderate level to save power. The “high UV” and “low UV” can be defined by thresholding or table-look-up.

Hardware Status

The image adjustment control circuit of the projection processor 124 could select a proper image adjustment algorithm according to hardware status of the projection device 120. In one embodiment, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm according to an available bandwidth of a memory device in the application processor 200 that is accessed by the projection processor 124. As other circuits in the application processor may share a same memory device (e.g. main memory, usually dynamic random access memory) with the projection processor 124. When the projection processor 124 detects an available bandwidth of the memory device is lower than a threshold, the image adjustment control circuit of the projection processor 124 may select the image adjustment that is less complicated or takes less bandwidth (i.e., accessing the memory device less frequently). Alternatively, the image adjustment control circuit of the projection processor 124 could disable the projection function to save the bandwidth of the memory device. On the other hand, when the available bandwidth is higher than the threshold, the image adjustment control circuit of the projection processor 124 may select a more complicated (i.e. bandwidth-starving) algorithm or remain projection function enabled to improve projection quality. FIG. 5 illustrates an implementation of controlling the projection of the projective display system 100 based on algorithms in Table A. In this implementation, when it is found that the available bandwidth is empty or lower than the threshold THR1, the projection function will be turned off by the image adjustment control circuit of the projection processor 124, when it is found that the available bandwidth is between threshold THR1 and threshold THR2, the image adjustment algorithm 3 that moderately accesses the memory (as it has moderate complexity level) may be selected by the image adjustment control circuit of the projection processor 124, and when it is found that the available bandwidth is higher than threshold THR2, the image adjustment algorithm 1 that may frequently access the memory (as it has highest complexity level) will be selected by the projection processor 124.

In another embodiment, the image adjustment control circuit of the projection processor 124 selects the image adjustment algorithm according to a battery status provided by the battery meter 290. When the battery life is detected short, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that is less complicated or consumes less power. Alternatively, the image adjustment control circuit of the projection processor 124 may turn off the projection function to extend the battery life. On the other hand, when the battery life is detected long, the image adjustment control circuit of the projection processor 124 may select the image adjustment algorithm that is more complicated or remains the projection function enabled to improve projection quality. FIG. 6 illustrates an implementation of controlling the projection of the projective display system 100 based on algorithms in Table A. In this implementation, when it is found that the battery is full, the image adjustment algorithm 1 that has highest power consumption level but best projection quality will be selected by the image adjustment control circuit of the projection processor 124, when it is found that the battery life is between threshold THR1 and threshold THR2, the image adjustment algorithm 3 that has moderate power consumption level and moderate projection quality level may be selected by the image adjustment control circuit of the projection processor 124, and when it is found that the battery life is lower than threshold THR2, the image adjustment control circuit of the projection processor 124 may turn off the projection function.

Image Context

According to image context, the image adjustment control circuit of the projection processor 124 could assign image adjustment algorithms at different complexity levels or projection quality levels to different contents of the input image. In this embodiment, since all image data will be firstly sent to the display processor 270, the display processor 270 is able to classify the image data. For example, when it is found that image data is sent from the video decoder 260, the display processor 270 may be aware of this image data is related to video playback. When it is found that image data is sent from the graphic engine 280, the display processor 270 can determines that this image data is related to web-browsing text. According to the information provided by the display processor 270, the projection processor may select suitable image adjustment algorithms for different contents.

ISP Parameters

The image adjustment control circuit of the projection processor 124 could select a proper image adjustment algorithm according to image signal processing (ISP) parameters corresponding to the input image if the input image is captured by an image senor of the set of sensors 210. The image adjustment control circuit of the projection processor 124 may refer to level of focus, level of exposure and/or ISO sensitivity about the input image according to information provided by the image signal processor 220. For the level of focus, the clearly focused input image and the blurred input image could lead to different image adjustment algorithms. For the level of exposure, the over-exposed input image, the under-exposed input image, and the properly-exposed input image may respectively lead to different image adjustment algorithms. For example, the over-exposed input image, the under-exposed input image may lead to a poor projection quality, the image adjustment control circuit of the projection processor 124 may therefore turn off the projection function. For level of ISO sensitivity, input image captured at different ISO sensitivity levels may lead to different image adjustment algorithms.

In the above embodiments, the image adjustment control circuit of the projection processor 124 may control the projection (i.e., determining whether to enable the projection function of the projective display system 100 as well as controlling the image adjustment on the source image on the projection source component 122) according to one type of the information including sensor information, hardware status, image context, and ISP parameters. However, in another embodiment of the present invention, the image adjustment control circuit of the projection processor 124 may control the projection according to multiple ones of the above information. For example, the image adjustment control circuit of the projection processor 124 may initially select an image adjustment algorithm having highest power consumption level and projection quality level due to information provided by the ambient light source. However, if, later, the image adjustment control circuit of the projection processor 124 finds that the battery life becomes quite low, the projection processor 124 may immediately turn off the projection function. That is, the image adjustment control circuit of the projection processor 124 may adaptively control the projection of the projective display system to have a good balance between user experience and power consumption.

Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least an implementation. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.

Thus, although embodiments have been described in language specific to structural features and/or methodological acts, it is to be understood that claimed subject matter may not be limited to the specific features or acts described. Rather, the specific features and acts are disclosed as sample forms of implementing the claimed subject matter.

Circuits in the embodiments of the invention may include function that may be implemented as software executed by a processor, hardware circuits or structures, or a combination of both. The processor may be a general-purpose or dedicated processor. The software may comprise programming logic, instructions or data to implement certain function for an embodiment of the invention. The software may be stored in a medium accessible by a machine or computer-readable medium, such as read-only memory (ROM), random-access memory (RAM), magnetic disk (e.g., floppy disk and hard drive), optical disk (e.g., CD-ROM) or any other data storage medium. In one embodiment of the invention, the media may store programming instructions in a compressed and/or encrypted format, as well as instructions that may have to be compiled or installed by an installer before being executed by the processor. Alternatively, an embodiment of the invention may be implemented as specific hardware components that contain hard-wired logic, field programmable gate array, complex programmable logic device, or application-specific integrated circuit, for performing the recited function, or by any combination of programmed general-purpose computer components and custom hardware component.

Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. 

1. A projection processor for a projective display system comprising: a receiving circuit, configured to receive information provided by a hardware element within a projection source device of the projective display system; and an image adjustment control circuit, coupled to the receiving circuit, and configured to adaptively control an image adjustment on an input image to generate a source image according to the information.
 2. The projection processor of claim 1, wherein the image adjustment control circuit determines whether to turn off a projection function of the projective display system according to the information.
 3. The projection processor of claim 1, wherein the image adjustment control circuit adaptively selects at least one of a plurality of image adjustment algorithms according to the information, and control the image adjustment to be performed according to the selected image adjustment algorithm.
 4. The projection processor of claim 3, wherein the image adjustment is performed by a circuit that is within or external to the projection source device.
 5. The projection processor of claim 3, wherein the plurality of image adjustment algorithms respectively cause the image adjustment to be performed at different power consumption levels.
 6. The projection processor of claim 3, wherein the plurality of image adjustment algorithms respectively have different complexity levels.
 7. The projection processor of claim 3, wherein the plurality of image adjustment algorithms are respectively optimized for different types of image adjustments.
 8. The projection processor of claim 3, wherein the plurality of image adjustment algorithms respectively activates different types of image adjustments.
 9. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to ambient light information provided by an ambient light sensor.
 10. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to distance information provided by a proximity sensor, wherein the distance information indicates a distance between a viewer and the projection source device.
 11. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to thermal information provided by a thermal sensor, wherein the thermal information corresponds to a temperature inside the projection source device.
 12. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to acceleration information provided by an accelerometer or a gravity sensor.
 13. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to orientation information provided by a gyroscope.
 14. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to pressure information provided by a pressure sensor.
 15. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to time and position information provided by a global position system (GPS) device.
 16. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to heart rate information provided by a heart rate sensor.
 17. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to information provided by a fingerprint sensor.
 18. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to ultraviolet information provided by an ultraviolet sensor.
 19. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to a type of the projection source component of the projection source device.
 20. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to available bandwidth information of a memory device of the projection source device.
 21. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to battery life formation of a battery of the projection source device.
 22. The projection processor of claim 3, wherein the image adjustment control circuit selects the selected image adjustment algorithm according to context of the input image.
 23. The projection processor of claim 3, wherein the image adjustment control circuit selects image adjustment algorithm according to the information provided by an image signal processor.
 24. The projection processor of claim 23, wherein the information provided by the image signal processor comprises at least one of level of focus, level of exposure, and level of ISO sensitivity regarding the input image.
 25. The projection processor of claim 1, wherein the image adjustment comprises at least one of image flipping, image segmentation, image enhancement, and distortion correction adjustments.
 26. The projection processor of claim 1,wherein the projection source device is rotatably mounted on a base of the projective display system, a projection surface of the projective display system is rotatably attached to the base; the projection surface mirrors the source image projected from a first side of the projection surface to form a virtual image on a second side that is opposite to the first side. 